A direct current-direct current (DC/DC) converter of the generic type is known from DE 102005023291 A1. On its input side, this converter incorporates a boost converter as well as a resonance converter so that, practically, there are provided two DC/DC converters or energy converter stages. This DC/DC converter has the advantage that the load of the switches is reduced in the resonance converter. In the event of discontinuous current, the switches turn on and off almost without any loss thanks to the incorporated resonance. Another advantage is its galvanic isolation. Through DC-AC converter clocking, high capacitive leakage currents may occur in photovoltaic (PV) generators. Galvanic isolation makes it possible to ground the photovoltaic generator and to eliminate these undesired currents as a result thereof. The boost converter located on the input side permits raising fluctuating input voltages, in particular lower input voltages. The direct voltage of a PV generator is often subject to strong fluctuations such as depending on the weather conditions, the day time or the season.
The disadvantage however is that a conducting boost converter diode also causes losses, when the boost converter is not operative.